Level 13 of OverTheWire’s Natas wargame is extremely similar to Level 12. The only difference now, is that it’s validating that the file is in fact an image. This however is flawed, as exif data can be faked.
It starts out with a similar upload prompt as last time.
The source code is super similar to last time.
<html> <head><link rel="stylesheet" type="text/css" href="http://www.overthewire.org/wargames/natas/level.css"></head> <body> <h1>natas13</h1> <div id="content"> For security reasons, we now only accept image files!